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Pre-alignment (baselining) uses the manual adjustments on top of the support structures.Relative alignment of Girder components is achieved and maintained through common-girder mounting checked by CMMGirder-to-Girder alignment is (remotely) controlled based on cam-shaft technology
During initial alignment [with focus on quadrupole and BFW positions]For quadrupole position control, i.e. beam steering during BBAFor compensation of ground motion effects etc.
Beam-Based-Alignment uses quadrupole magnets in two ways:1) via off-center dipole fields. [Change is done through cam-based girder
motion, which will align all girder components to the beam. Minimum motion range covers area of circle with 700 µm radius ]
2) via dipole trim-windings on Quadrupole Magnets (used for fine adjustments.) [Range equivalent to ±100 µm of Quad motion]
Pre-alignment (baselining) uses the manual adjustments on top of the support structures.Relative alignment of Girder components is achieved and maintained through common-girder mounting checked by CMMGirder-to-Girder alignment is (remotely) controlled based on cam-shaft technology
During initial alignment [with focus on quadrupole and BFW positions]For quadrupole position control, i.e. beam steering during BBAFor compensation of ground motion effects etc.
Beam-Based-Alignment uses quadrupole magnets in two ways:1) via off-center dipole fields. [Change is done through cam-based girder
motion, which will align all girder components to the beam. Minimum motion range covers area of circle with 700 µm radius ]
2) via dipole trim-windings on Quadrupole Magnets (used for fine adjustments.) [Range equivalent to ±100 µm of Quad motion]
Main girder components includeBeam Finder Wire (BFW)Undulator strongback arrangement mounted on horizontal slidesVacuum chamber supportBPMQuadrupoleMounts for the Wire Position Monitor (WPM) systemSensors of the Hydrostatic Leveling System (HLS) Diagnostics components
The undulator strongback arrangement (Segment) is mountable on and removable from the girder with the vacuum chamber in place and without compromising the alignment of the vacuum chamberSegments will be taken off the girder for magnetic measurementsSegments will be interchangeable without the need for the CMMThe complete girder assembly will be aligned on the Coordinate Measurement Machine (CMM).
Main girder components includeBeam Finder Wire (BFW)Undulator strongback arrangement mounted on horizontal slidesVacuum chamber supportBPMQuadrupoleMounts for the Wire Position Monitor (WPM) systemSensors of the Hydrostatic Leveling System (HLS) Diagnostics components
The undulator strongback arrangement (Segment) is mountable on and removable from the girder with the vacuum chamber in place and without compromising the alignment of the vacuum chamberSegments will be taken off the girder for magnetic measurementsSegments will be interchangeable without the need for the CMMThe complete girder assembly will be aligned on the Coordinate Measurement Machine (CMM).
A misaligned undulator will not steer the beam. It will just radiate at the wrong wavelength.The BFW allows the misalignment to be detected. (also allows beam size measurements)
A misaligned undulator will not steer the beam. It will just radiate at the wrong wavelength.The BFW allows the misalignment to be detected. (also allows beam size measurements)
Manual Adjustability:Rough CAM position adjustability relative to fixed support.ranges: x (12 mm); y (25 mm); z (12 mm)Quadrupole, BFW, BPM, Vacuum Chamber, and Segment adjustability to Girder. ranges: x (>1 mm); y (>1 mm); z (>1 mm)
Remote Adjustability:Girder: x, y, pitch, yaw, roll [1.5 mm x and y]
Enables alignment of all beamline components to the beam axis.Roll motion capability is to be used to keep roll constant
Undulator: x [ 80 mm range]Provides control of undulator field on beam axis.Horizontal slide stages move undulator strongback independent of Girder and vacuum chamber.
Manual Adjustability:Rough CAM position adjustability relative to fixed support.ranges: x (12 mm); y (25 mm); z (12 mm)Quadrupole, BFW, BPM, Vacuum Chamber, and Segment adjustability to Girder. ranges: x (>1 mm); y (>1 mm); z (>1 mm)
Remote Adjustability:Girder: x, y, pitch, yaw, roll [1.5 mm x and y]
Enables alignment of all beamline components to the beam axis.Roll motion capability is to be used to keep roll constant
Undulator: x [ 80 mm range]Provides control of undulator field on beam axis.Horizontal slide stages move undulator strongback independent of Girder and vacuum chamber.
Component Position Monitoring Systems(Alignment Diagnostics System – ADS)
UltrasoundProbe
Fiducial
Reference surfaces
• Resolution < 100 nm in X & Y direction• Instrument Drift < 100 nm per day• Moving Range ±1.5 mm in X & Y direction• Accuracy 0.1 % of full Scale • Availability Permanent, no interrupts
Wire Position Monitor system (WPM)
Hydrostatic Leveling System (HLS)
• Precision < 1 m• Instrument Drift ~1-2 m / month• Accuracy < 0.1 % of full Scale
Capacitive Sensor
Ultrasound Sensor• Precision < 0.1 m • Instrument Drift potentially no drift• Accuracy < 0.1 % of full Scale
HLS 1 HLS 2
HLS 4 HLS 3Beam
pitch
rollheight
Ceramic plate
ElectronicSensing Electrode
eAir
eWater DWater
DAir
X and Y, can be measuredRoll, Jaw & Pitch can be calculated.
Zone 2Zone 2 ( (tt > 1 hr, > 1 hr, PP//PP00 > 90%, non-invasive) > 90%, non-invasive)• Maintain component alignment based on ADSMaintain component alignment based on ADS
Correction Zones
Zone 3Zone 3 ( (tt > 24 hr, > 24 hr, PP//PP00 > 90%, non-invasive) > 90%, non-invasive)• Maintain component alignment based on ADSMaintain component alignment based on ADS• Possible x-ray pointing correctionPossible x-ray pointing correction
Zone 4Zone 4 ( (tt > 1 mo, > 1 mo, PP//PP00 > 75%, machine time) > 75%, machine time)• One iteration of BBA (<1 hr)One iteration of BBA (<1 hr)
Zone 5 (Zone 5 (tt > 6 mo, shut-down) > 6 mo, shut-down)• Reset movers set to zero and manual realignment (1 wk)Reset movers set to zero and manual realignment (1 wk)• Full 3 iterations of BBA (~3 hrs)Full 3 iterations of BBA (~3 hrs)
The X-ray-FEL puts very tight tolerances on magnetic field quality, electron beam straightness, and Segment alignment.
These tolerances can be achieved through Beam Based Alignment (BBA) procedures based on BPMs and Quadrupoles (with energy scan) as well as BFWs.
Relative component alignment to required tolerances will be achieved through common girder mounting.
Main tasks of the conventional alignment and motion systems areComponent fiducialization and alignment on girder
Conventional alignment of girders in Undulator Hall as prerequisite for BBA
The Alignment Diagnostic System measures and enables the correction of girder movement due to ground motion, temperature changes, and CAM mover changes.
A strategy is in place for using the monitor systems and controls to establish and maintain a straight trajectory.
The X-ray-FEL puts very tight tolerances on magnetic field quality, electron beam straightness, and Segment alignment.
These tolerances can be achieved through Beam Based Alignment (BBA) procedures based on BPMs and Quadrupoles (with energy scan) as well as BFWs.
Relative component alignment to required tolerances will be achieved through common girder mounting.
Main tasks of the conventional alignment and motion systems areComponent fiducialization and alignment on girder
Conventional alignment of girders in Undulator Hall as prerequisite for BBA
The Alignment Diagnostic System measures and enables the correction of girder movement due to ground motion, temperature changes, and CAM mover changes.
A strategy is in place for using the monitor systems and controls to establish and maintain a straight trajectory.